Switch apparatus with movable contact brush assembly



1964 J. PARSTORFER SWITCH APPARATUS WITH MOVABLE CONTACT BRUSH ASSEMBLY Filed May 17. 1960 2 Sheets-Sheet l IN VEN TORS.

JOHN PARSTORFER Dec. 1, 1964 J. PARSTORFER 3,159,724

SWITCH APPARATUS WITH MOVABLE CONTACT BRUSH ASSEMBLY Filed May 17. 1960 2 Sheets-Sheet 2 INVENTORS. JOHN PARSTORFER United States Patent The present invention relates to electrical switch apparatus. More particularly it has to do vith a contact brush assembly and with means for moving the assembly into and out of operative relationship with electrical switch program apparatus for rapid switching or exchanging of programmed input-output connections from one electrical circuit to another.

Various forms of drum type switch apparatus have been developed in the past for providing multiple electrical input-output connections for various uses, such for e"- nniple, as in automatic telephone exchanges, electrical advertising signs, etc. Such apparatus many times comprises a rotatable drum or cylinder having mounted thereon conducting or commutating segments, and wipers or brushes associated with the respective commutating segments adapted to engage the same at predetermined points in the rotation of the cylinder about its axis of rotation. Generally the programs for these switches at fixed in character or, if the program is alterable at all, it is only changed with difiiculty. It is often difiicult to change the switch program without damaging the program portions of the switch apparatus without making it necessary to disconnect the brush contact carrier from its support or at least disassembling the brush contact assembly. Additionally, when diiferent switching combinations or dilferent sequences of switching combinations are desired, extensive time-consuming adjustments must often be effected making the over all device one of a relatively low order of etllciency.

it is an important object of the present invention therefore, to provide switching apparatus which overcomes the foregoing problems in a simple, economical and highly efficient manner.

Another important object of the present invention is to provide a brush contact carrier which when moved from retracted to operating position automatically aligns itself with the switch program apparatus.

Still another object of the invention is to provide a switch contact carrying assembly.

An additional object of the invention is to provide a switch contact carrier assembly which may be disconnected from the switch program apparatus siiiply and etficiently without disassernbly of the whole switch structure.

A further object of the invention is to provide a novel brush contact assembly formed by pairs of interfitting contact carrying members which in their assembled condition automatically orient the electrical contacts thereof in spaced apart parallel rows.

A still further object of the invention is to provide an electrical contact carrier for a rotary program type switch wherein the switch program member is automatically locked in operating position when the contact carrier is engaged therewith and is released for removal therefrom when the contact carrier is retracted out of contact therewith.

in accordance with the foregoing obiects and first briefly described the invention comprises a brush contact carrying frame for a rotary switch program apparatus which is movably positionable toward and away from a switch program drum whereby its contacts are retracted out of engagement with the switch segments of the drum or extended into position engaging the drum Patented Dec. 1, 1954 segments, and when in the latter position complete multiple electrical input-output circuit connection for said apparatus.

The novel features which are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself both as to its construction and its method of operation, together with additional objects and advantages thereof will be best understood from the following description of the preferred embodiment when read in conjunction with the accompanying drawings in which:

l is an exploded perspective View of the switch program apparatus including the preferred embodiment of the present invention;

FIG. 2 is a sectional view of the brush contact assembly of FIG. 1;

PEG. 3 is a sectional side elevational view along the line 33 of PEG. 2 illustrating the movable brush contact frame for the present invention;

FIG. 4 is a sectional view of the brush structure of the present invention in disassembled condition;

1G. 5 is a fragmentary sectional view illustrating a portion of the brush structure or assembly of FIG. 4 in its assembled condition;

6 is a detail sectional view along the line 66 of FIG. 5;

PEG. 7 is a detail view along the line 7- 7 of FIG. 5; and

FIG. 8 is a detail perspective view of an individual brush contact for the present invention.

Referring to FIG. 1 the switch apparatus in accordance with the preferred embodiment of the pres nt invention is illustrated in conjunction with rotary switch apparatus of the type described and claimed in copending United States Patent application, Serial No. 27,405, filed May 6, i960 and new US. Patent No. 3,071,661, in the names of John T'arstorfer and Alvin W. Gellert, entitled Switch Apparatus, and assigned to the ea: .c assignee as the present invention. Such apparatus includes a substantially cylindrical, hollow, barrel or drum-like member It), detachably engageable with and mounted for rotation upon, an upstanding compound pedestal-like supporting member 12, which is supported for rotation on a base or frame 14 of the apparatus. The drum It) is adapted to be rotated intermittently in step-by-step fashion by means of a Geneva star or gear wheel 16 to which it is secured. The wheel it? is rotatably mounted on the frame 14 and drivingly coupled through a control mechanism 18 and a gear train 29 to a drive motor 22.

Demountably disposed in spoke-like radial arrangement around and recessed within the hollow interior of ,iurality of detachably removable switch program segments Adjacent the periphery of the drum 10 is disposed a pivotally retractable brush contact carrier frame assembly 26 including a plurality of banks 27 of brush contact members adapted to be engaged with and to be disengaged from the electrically conductive elements of the switch program segments 24, as will be explained herein presently. The assembled apparatus may be enclosed within a suitable housing (not shown) secured in a conventional manner to the base or platform 14-.

The drum member 1% includes oppositely disposed annular disc-like members which together form upper and lower spaced apart drum heads 39 and 32 respectively therefor. The upper head 3% is attached to a shallow, circular, inverted cup-shaped clamping cap member 34, an upstanding portion 36 of which projects slightly above the inner peripheral opening 33, in member 3%. Member 34 is provided with a peripheral flange 4t) and a hub 48, for purposes to be explained presently. The annular head 39 is secured to the member 34, as by bolts (not shown) extending into and through flange 4t) and into the inner periphery of the member 343.

The drum ltl includes inner and outer hollow cylindrical sleeve-like members 54 and 55 respectively, which are disposed in spaced apart concentric relation. The inner sleeve member 54 has one end 58 thereof engaged over the outer peripheral surface of hub .3, as by being pressfitted thereto. The opposite end of sleeve 54 is received in a circular groove at"; in drum head 32. Bolts 74 secure the drub head members 3t) and 32 to their respective opposite ends of the sleeve 55. The lower drum head 32 is provided with an aperture 75 therein, intermediate the two members 54 and 55 for purposes to be explained hereinafter. Each of the members 3% and 32 is provided with a plurality of spoke-like radial notch-es or grooves '7676' intermediate lands 77-77 respectively, disposed in confronting relation as shown, for purposes to be described. 7

The star wheel or gear 26 which in the present embodiment' comprises a relatively'thin, disc-like member, may be fabricated from any suitable rigid material such as Synthane-nylon fibre, laminate, etc. The outer periphery of the gear 16 is provided with a plurality of radial notches or slots 112 alternating with arcuately shaped indentations 114 forming drum indexing means, for purposes to be explained hereinafter. In the preferred embodiment herein illustrated, twenty-four notches and twenty-four indentations are employed. It should be apparent however, to those skilled in the art that other and varied combinations of indentations and notches could be used.

The upper surface 1-1 5 of the gear is provided with milled or drilled clearance openings or depressions 118 therein concentric with attachment bolts, not shown, for the lower drum head 32. A drum position locating pin 119, is pressed-fitted or otherwise disposed in the wheel 16 adjacent the base of the pedestal l2 and is receivable in the hole 75 in the drum 1% thus orienting the drum on the drive means for reasons which will become more apparent as the description proceeds. A plurality of ape tures 156 circularly disposed in the member 34 and concentric with'openings iSS-in the pedestal 12 permit bolts 16!? to engage and secure the drum it? to the pedestal 12 for incremental or step-by step rotation as will be described hereinafter.

The brush contact carrier assembly 26 in accordance with the present invention is located adjacent to the periphery of the drum it in a manner such that the banks 27 of brush contact elements may be engaged with the switch segments 24 in a manner which will become more fully apparent as the present description proceeds. The assembly 26, FIG. 3, includes upper and lower irregularly shaped members 152 and 164 disposed in spaced apart relation at one end of the frame member 14 by means of a rod or dowel, not shown, secured therebetweenas by screws and an upstanding lockpost 17h disposed between members ldZ and line. The lower end 172 of the post 170 is secured to member 164 as by means of thescrew 174. The upper member 162 is provided at its rigl'ltward end 176 with an aperture 17% and a circular depression or recess 18% formed therein concentric with aperture 178 into which the upper end 132 of the lockpost 179 is press-fitted.

The top portion of the lockpost ilil is drilled or otherwise hollowed interiorly lengthwise to provide an elongated chamber 184 into which a locking plunger pin 186 is slidably disposed. The lower end 188 of pin 186 is'undercut to provide a short shank 1% around which the end 192 of a coil spring 394 is received so as to seat against the shoulder 1%. The opposite end 198 of the. spring 194 is seated on the bottom 2% of chamber 184. The spring is pretensioned to eifectively bias the plunger 186 upwardly and outwardly from the chamber 18 A transverse opening ZtlZ in the lockpost 1% proportion of the drum and in which the drum ii is thus.

vides sufiicient vertical clearance therein to permit a horizontally disposed cross pin 264 secured transversely through the plunger 1% to be movable for a short distance vertically up and down within the chamber 184, for purposes to be described presently. The unrestrained upper end of the plunger lfidis adapted to project vertically out of the chamber 184 a short distance through the aperture 178 in the upper member 162.

An open substantially rectangular brush contact supporting frame 2% for the brush contacts 27, is milled or otherwise provided with an inner peripheral flange 2%, for purposes to be explained hereinafter and is pivoted at its bottom leftward corner 2%, FIG. 3, on a pin 21% press-fitted therein and projecting into an aperture 212 in the lower memberrld i. The upper leftward corner 214 of the member 2% carries a pivot pin 216 projecting into and through an aperture 213 in the upper member hi2 concentric therewith and isisecured to an irregularly s raped handle or locking member 22%) as by being pressfitted thereto, the exposed end of the pin being peaned over, FIG. 3, to prevent dislodgement therefrom. The handle 221i), PEG. 3, carries a pin 221 intermediate the ends thereof depending through an arcuate aperture 222 in member 162 and press-fitted or otherwise secured in the top 223 of the brush frame support 2%. By virtue of the foregoing construction the frame 2% is arcuately, pivotally movable by means of the handle 2% about the upper and lower pivots 2-16 and 21%) between forward and rearward limit or stop members 224 and 226, as seen most clearly in FIG. 2.

The rightward portionZZil of the free side, ofthe frame 2% is provided with a release notch'23tl intermediate the. ends thereof.

tally disposed pin 234 as the release or handle member.

22b is ai'cuately moved, FIG. 2, from its full line position wherein the handle member 22% overlies a peripheral effectively restrained thereby from removal from pedestal 12, accidentally or otherwise, to the dotted line position wherein the member 22% is withdrawn from the aforementioned overlying position and in which the drum may 3' be effectively removed and thebanlis of brushes 27 automatically disengaged from contact" with the switch segments 24. Since the brush frame 2% and the handle 22!) move together this novel arrangement prevents the accidental damage to the brushes which might occur if removal of the drum were attempted before the brushes were moved beyond the rotational path of the drum.

As is apparent in FIG. 2, the cross pin 2% performs a dual function in conjunction with the two stop members 224426. In the forward brush engaging position the cross pin 234 locks the frame 206 against the stop 224 and prevents the frame from being accidentally moved away from the drum 1b. In the rearward brush disengaged position the cross pin Zild'locks the frame against the rear stop member 226 thus avoiding an accidental contact of the brushes 2'7 with the periphery of the drum during removal thereof.

A particularly novel feature of the invention will now be described. As seen in FIGS. 2 through 8 inclusive, the contacts of the banks 27 of contact brushes of the preferred embodiment herein described, comprise individual, substantially elongated U-shaped wire-like elementsZZtZ, FIG. 8, pre-formed and bent so that the parallel legs 23 5-234 thereof are disposed in spaced apart relation throughout their length, as seen more clearly in the sectional view of FIG. 6. The free ends 236236 of the parallel legs are arcuately bowed to provide a wiping contact. 233 for purposes to be explained presently. An efiicient and relatively inexpensive fabrication technique is employed in the present invention to produce each of the contact brush carriers or bars 24% into which the brushes are received as will now be described in connection with FIGS. 4-7 inclusive. 7

Dielectric material, such for example, as epoxy resin or similar material, which may be hot or cold poured as desired, is poured into a mold, not shown, within which a row of contacts 232 are angularly oriented. For example, at 45 to the horizontal as seen in FIG. 4. The wiping contact end 238 of each member is adapted to project outwardly away from the surface of the bar 240 a willclent distance so as to engage the contact of the switch segments as will be described later on. The U-shaped end of alternate contacts 232 is bent at right angles out of the plane of the contact as shown, thus providing means for securing the contact elements within the resinous block 240 and additionally providing a simple, inexpensive and readily accessible electrical junction point, FIG. 7, for attachment thereto of the lead wires, not shown. In this manner the contact elements may each be interconnected with a junction block or other electrical connecting devices for use with associated electrical circuitry such for example as a computer. The edges 244 of the bars 244) are provided with a double tongue and groove arrangement 246 and 248 respectively thus to form interfitting edge portions. As is clearly apparent in FIG. 4, the dielectric members 249 are identical in configuration thus reducing the cost of design and fabrication since only one set of tongue and grooves must be produced in each member 246. The difference between the two members of FIG. 4 results from the angular orientation of the contacts, i.e., the contact elements of the uppermost member are oriented to project out of the block in a direction opposite to that of the lowermost member. As is seen in FIG. 5, when the two blocks are interfitted by means of their interengaging tongues and grooves and thereafter adhesively joined as by glue or other bonding material, the contact elements 232 are automatically aligned in two parallel spaced apart rows with their wiping contacts 238 oriented in the same direction thus avoiding the necessity for costly jigs, fixtures or manual adjustments on the part of the fabricator.

During construction one of the tongues 246 of each of the blocks 240 is chamfered as indicated by the reference character 249 such that the angular orientation of the contact elements may persist unintemlptedly from the direction toward their arcuately curved ends without interference from the mating block when the latter is engaged therewith, as seen in FIG. 5. The foregoing structural arrangement standardizes the construction of the contact blocks which may be produced relatively simply and eliiciently. The g'oined blocks are thereafter placed in the peripheral groove formed by the flange 297 (FIG. 2) of the frame support 2% and attached therein as by the countersunk bolts 25%. This construction provides an efiicient means for clnnging or replacing contact elements to suit the particular purposes of the electrical circuits with which the apparatus is to be employed.

Additionally, it is to be noted that by virtue of the foregoing arrangement, as shown most clearly in FIG. 3, the brush contact frame member and its handling element 229 permit easy access to the contact frame while preventmg accidental dislodgement of the drum or damage to the fine wire brush contact elements. When it is desired to remove either the drum from the assembly or the stag rnents from the drum the hold down screws 16% are removed after which the handling member is arcuately rotated fronrits full line drum overlying restraining and bcklllg Position to its dotted line position FIG. 2, with awlng e handle trom its drum overlying position and carrying the brush contact members out of engagement with the contact segments thereby permitting the drum to be lifted off the pedestal 12.

The rotary program switch apparatus it) is provided with twenty-four program sections 24 each of which in this embodiment includes ninty-six contact elements providing a total of two thousand three hundred and four contacts. Each segment includes a pair of parallel spaced apart planar members and 2521b which are assembled together in the manner described and claimed in copending United States Patent application, Serial No. 29,049, filed May 13, 1960, entitled Switch Apparatus and Method of Manufacture in the name of John Parstorfer and assigned to the same assignee as the present invention. Segments 24, FIG, 4, are then slid into respective upper and lower grooves 76-76 in the drum periphery so that the ends 294-294 of bars 270 ride over lands 7'7 77' adjacent each groove. Bolts 2%, received through the channel 288 and threaded into apertures in upper and lower ends of the outer sleeve member 56, secure the segments to the drum and prevent their accidental dislodgement or detachment therefrom when the drum is rotated by means now to be described.

As before mentioned, the switch apparatus is driven by a Geneva type escapement mechanism, ES. 1, providing intermittent step-by-step rotation of the drum it. The star drive wheel 16 including the peripherally disposed notches and arcuate cutouts 112, 114 respectively therein is engaged by a multi-toothed drive wheel sea. An upstanding discontinuous arcuate ridge or flange 5th? is adapted to engage the arcuate portion 114 of the star wheel 16, during rotation of the latter, as wi l he described shortly.

A drive pin 324 secured to the drive wheel 3% has one end projecting upwardly therefrom to be received in the slots 112 thereby to step the wheel 16 as will be more clearly set forth hereinafter.

A control switch, not shown, is disposed adjacent to the drive motor 22 and includes an actuator arm 32% which extends arcuately away therefrom into the path of movement of the drive pin 324. The output shaft of the motor 22 carries a pinion 336 rotatively coupled to the output drive gear 338 through a transfer idler gear, not shown. The output drive gear 338 is secured to the input shaft 341 of the control member 18, e.g., an electromagnetic clutch (not shown). The output shaft 34%? of the clutch is connected by a flexible coupling 342 to drive a short shaft 344 carrying a pinion 345 on its lower end in operable engagement with the Geneva drive gear 36% for rotating the same in response to energization of the drive motor 22, as will now be described.

When it is desired to operate the present rotary program switch apparatus the drum 10 is loaded with the desired number of switch program segments 24, the brush contact holder 25 is retracted to its broken line position, FIG. 2. The loaded drum is then lowered over the pedestal 12 so that the drum position locating pin 119 is received in the aperture '75 in the lower drum head 32. Bolts 16% are threaded into mating openings 156 and 15S and tightened thereby securing the drum to the pedestal. The brush holder 26 is then moved from its retracted broken line position to its full line position, FIG. 2, wherein the handle member 22%) overlies the periphery of the drum etleotively locking the drum against accidental dislodgement or removal and the electrical contact brushes 232 may engage the wipe across respective ones of the input and output electrical contacts of the switch segments as the drum is rotated thus to electrically interconnect different ones of the brushes as the drum is stepped from one to another of the segments, according to the program desired.

Energization of control 18 causes constantly running motor 22 to rotate gear Sill) through the gear train hereinbefore described. Rotation of gear 3% in the direction of the arrows 362 causes the ridge 3% to rotate within the arcuate cutout 114 retaining the star wheel 16 in a y condition. The pin 324 as gear 3% rotates Wlll enter the next leftward notch 1 2 thereafter moving the wheel 16 one step clockwise in the direction of the arrow 364. Continued rotation of gear 309 causes th pm 324 to leave notch 112 while the discontinuous ridge 306 once again engages and rides around the next cutout 116. Pin 324 then strikes the actuator 325 disengaging the control mechanism 13 to halt the positiv advance of the wheel 16.

What is claimedis:

1. An electrical brush contact supporting assembly for a movable program switch comprising, abase member, a demountable, rotatable program switch disposed on said base, an open rectangular frame, means pivotally mounting said frame on said base member in a manner permitting said frame to move in an arcuate path between advanced and retracted terminal positions relative to said program switch, a plurality of resilient electrical conductors, dielectric means mounting said conductors on said frame with one end portion of each of said conductors extending angularly away therefrom, in parallel spaced apart rows and through the opening in said frame, and means to lock said frame relative to said base in either of said terminal positions.

2. An electrical brush contact supporting assembly for a rotary program switch comprising, a base member, a driven member, a demountable rotatable drum disposed on said driven member, an open rectangular frame, means pivotally mounting said frame on said base member in a manner permitting said frame to move in an arcuate path between advanced and retracted terminal positions relative to said drum, a plurality of resilient electrical conductors, dielectric means mounting said conductors on said frame with one end portion of each ofsaid conductors extending angularly away therefrom, in parallel spaced apart rows and through the opening in-said frame, and means to lock said frame relative to said base in either of said terminal positions.

3. A construction according to claim 2 and wherein said last named means includes means preventing said drum member from being removed from said driven member when said frame member is in its advanced condition, yet permitting said'drum'member to be removed from said driven member when in-saidretracted condition.

4. A construction in accordance with claim 2 wherein said last means is a handle for moving said frame between its advanced and retracted positions.

5. An electrical'switch assembly comprising, a rotatable drum having-a plurality of spaced fixed electrical contacts around its peripheral surface, a contact carrying frame disposed adjacent to the periphery of said drum, means to move said frame arcuately from a retracted position away from said drum to an advanced position toward said drum, a dielectric member secured to and movable with said frame, a plurality of wiping contacts carried by said dielectric member, and means to lock said frame in its retracted or advanced position thus to'move' and lock said wiping contacts into and out of positions engaging said fixed contacts.

6. An electrical switch contact assembly comprising, a first member having a plurality of notches and projections thereon, said first member being provided with a plurality of electrically conductive contact members ex tending angularly away therefrom and a second member substantially identical to said first member and having a plurality of notches and-projections thereon, said second member being likewise provided with a similar plurality of electrically conductive contact members extending angularly therefrom, the contact members of said first member extending in an opposite direction with respect to the contact members of said second member whereby when the notches of'one of said members are interfitted with the projections of the other of said members, theelectrically conductivecontacts of both members aresimilarly angularly oriented.

7. The construction in accordancewith claim 6 wherein one end portion of alternate ones of said contact members is angularly oriented with respect to the remainder thereof thus to restrain said contact from accidental dislodgement or removal from said first and secondmembers and to provide circuit attachment means therefor.

8. An electrical brush contact assembly for a rotary program switch comprising, a'first member'having' at least one straight edge in which a plurality of notches and projections are formed, said first member being provided with a plurality of electrically conductive contact members extending angularly therefrom, anda second member substantially'identical to' said first member and having a plurality of notches and projections along a straight edge portion thereof, said second member being. likewise provided with a similar plurality of electrically conductive contact members extending angularly therefrom, the contact members of said first member extending in anopposite direction with respect to the contact members of saidsec- 0nd member whereby when the notches of one of said members are interfitted with the projections of the other of said members, the electrically conductive contact members of both are similarly angularly oriented in parallel rows, said notches being so formed as to prevent other orientation.

References Cited in the file of thispatent UNETED STATES PATENTS 900,781 Reist Oct. 13, 1908 1,228,710 Steen June 5, 1917 2,475,276 Briggs July 5, 1949 2,501,456 Thias et a1 Mar. 21, i) 2,910,552 Lindgren Oct. 27, 1959 

1. AN ELECTRICAL BRUSH CONTACT SUPPORTING ASSEMBLY FOR A MOVABLE PROGRAM SWITCH COMPRISING, A BASE MEMBER, A DEMOUNTABLE, ROTATABLE PROGRAM SWITCH DISPOSED ON SAID BASE, AN OPEN RECTANGULAR FRAME, MEANS PIVOTALLY MOUNTING SAID FRAME ON SAID BASE MEMBER IN A MANNER PERMITTING SAID FRAME TO MOVE IN AN ARCUATE PATH BETWEEN ADVANCED AND RETRACTED TERMINAL POSITIONS RELATIVE TO SAID PROGRAM SWITCH, A PLURALITY OF RESILIENT ELECTRICAL CONDUCTORS, DIELECTRIC MEANS MOUNTING SAID CONDUCTORS ON SAID FRAME WITH ONE END PORTION OF EACH OF SAID CONDUCTORS 